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Due to the significance of atmospheric HONO as a reservoir for radicals and the presence of substantial unknown sources of HONO, there is a pressing need for accurate and consistent measurement of its concentration. In this study, we compared the measurements obtained from the monitor for aerosols and gases in ambient air (MARGA) based on wet chemical method with those from the incoherent broadband cavity-enhanced absorption spectroscopy (IBBCEAS) based on optical method to assess the suitability of the MARGA instrument for accurate HONO detection. The diurnal patterns obtained by the two instruments are similar, with peaks at 8 a.m. and lows at 5 p.m. Over the course of the observation period, it was often observed that HONO concentrations recorded by the MARGA instrument consistently exceeded those obtained through the IBBCEAS technique, accounting for approximately 91.33% of the total observation time. Throughout the entire observation period, the R2 value between the two instruments was 0.49, indicating relatively good correlation. However, with a slope of only 0.27, it suggests poor agreement between the two instruments. Furthermore, the R2 and slopes between the two instruments vary with the seasons and day-night. The larger the quartile values of NO 2 , NH 3 , and BC, the greater the slopes of both MARGA and IBBCEAS instruments, and the higher the concentrations of NO 2 , NH 3 , and BC (indicator of semivolatile oxidizable hydrocarbons), the greater the differences between the two instruments, all indicating that NH 3 may promote the reaction of NO 2 with semivolatile oxidizable hydrocarbons to produce HONO. The O 3 with its strong oxidizing properties may cause underestimation in the MARGA instrument by oxidizing NO 2 − to NO 3 − in the absorbing solution. It is challenging to derive a universal correction formula due to the interference of various chemical substances. Hence, MARGA should not be used for HONO research in the future. [Display omitted] • Year-long HONO measurements show NH 3 interferes with MARGA by promoting NO 2 reactions, making it unfit for HONO monitoring. [ABSTRACT FROM AUTHOR]

The Co-Ni bimetal based catalysts had been considered as promising candidates for the CO 2 reforming of CH 4 reaction due to the Co-Ni synergistic effect. In order to further improve the catalytic property and anti-coke performance, Mg and Ca alkaline-promoted Co-Ni bimetal ordered mesoporous materials had been designed and fabricated by one-pot evaporation induced self-assembly method, which could be directly used as the catalysts for CRM reaction. These mesoporous catalysts were systematically characterized by XRD, N 2 adsorption-desorption analysis, TEM, EDS, XPS, H 2 -TPR, and CO 2 -TPD. It was found that the materials calcined at 700 °C could successfully maintain relatively large surface areas (120–212 m 2 /g), big pore volumes (0.27–0.48 cm 3 /g), and narrow pore size distribution (9.5–11.0 nm), which could accommodate the gaseous feedstock with sufficient accessible Co-Ni active centers. Meanwhile, the Co-Ni active centers were in situ introduced into and confined by the ordered mesoporous framework by one-pot strategy, which could effectively inhibit the thermal agglomeration of Co-Ni nanoparticles. The presence of the Mg and Ca basic modifiers greatly intensified the surface basicity and enhanced the chemisorption of CO 2 , which would be beneficial to the activation of CO 2 and the acceleration of the coke-elimination process. The present Co-Ni bimetal catalysts promoted by Mg and Ca displayed higher catalytic activities and better coke-resistant performance than the Co-Ni reference catalyst without any alkaline modification. Therefore, the present Mg and Ca alkaline elements promoted Co-Ni bimetal based ordered mesoporous catalysts promised potential candidates for CRM reaction. [ABSTRACT FROM AUTHOR]

• We analyze the limitations of directly applying the high-order multi-hop neighbors to graph neural networks, including computational inefficiency and limited representation ability of the multi-hop neighbor. • We propose a Markov Clustering Regularized Graph Neural Network (MCMGN) to overcome the limitations. By introducing iterative approximation and Regularized Markov Clustering strategies, the proposed model improves the performance of the multi-hop graph neural network for graph-level representation learning. • Extensive experimental results have verified the effectiveness of the proposed Markov Clustering Regularized Graph Neural Network for graph classification on eight graph benchmark datasets. • In this paper, we develop a Markov Clustering Regularized Multi-hop Graph Neural Network (MCMGN) to overcome the two limitations of higher-order multi-hop graph neural network, i.e., computational inefficiency and limited representation ability of multi-hop neighbor. We analyze the reasons of these two limitations in detail and give the corresponding solutions, i.e., iteration approximation and Markov Clustering regularized approaches, to achieve a excellent performance for graph-level representation learning. To evaluate the effectiveness of the proposed model, we carry out a series of experiments including the comparison with existing models, prune threshold comparison, impact of the number of iteration, impact of the normalization of node feature matrix, and computation cost comparison. Extensive experimental results strongly demonstrate the superiority of MCMGN in predictive performance for graph-level representation learning. [Display omitted] Graph Neural Networks (GNNs) have shown great potential for graph data analysis. In this paper, we focus on multi-hop graph neural networks and aim to extend existing models to a high-order multi-hop form for graph-level representation learning. However, such a directly extending method suffers from two limitations, i.e., computational inefficiency and limited representation ability of the multi-hop neighbor. For the former limitation, we utilize an iteration approach to approximate the power of a complex adjacency matrix to achieve linear computational complexity. For the latter limitation, we introduce the Regularized Markov Clustering (R-MCL) to regularize the flow matrix, i.e., the adjacency matrix, in each iteration step. With these two strategies, we construct Markov Clustering Regularized Multi-hop Graph Neural Network (MCMGN) for graph-level representation learning tasks. Specifically, MCMGN consists of a multi-hop message passing phase and a readout phase, where the multi-hop message passing phase aims to learn multi-hop node embedding, and then the readout phase aggregates multi-hop node representations to generate graph embedding for graph-level representation learning tasks. Extensive experiments on eight graph benchmark datasets strongly demonstrate the effectiveness of Markov Clustering Regularized Multi-hop Graph Neural Network, leading to superior performance on graph classification. [ABSTRACT FROM AUTHOR]

Volatile organic compounds (VOCs) are critical precursors of photochemical smog. Quantitatively evaluating the VOC sources and their contributions to ozone formation provides valuable information for photochemical pollution abatement. However, due to the fast oxidization of VOCs during transport in the atmosphere, source apportionment via receptor models using measured VOC data inevitably has a systematic deviation. In this study, we conducted a field measurement of VOCs at a suburban site in Beijing and evaluated the influences of photochemical oxidization on VOC source contributions. The initial VOC concentration, defined as the sum of measured VOC concentration and their photochemical losses. The real-time photochemical age-based parameterization method and a sequential reaction model were applied to characterize the photochemical loss of VOCs. Also, the photochemical loss of VOCs was considered in the he positive matrix factorization (PMF) model. Photochemical losses, on average, accounted for 5.6% of total VOCs (TVOCs) and 59.2% of alkenes, indicating that the impact of photochemical reaction cannot be ignored. Alkanes were the most significant contributors to both measured and initial TVOCs, while the alkenes and oxygenated volatile organic compounds (OVOCs), especially ethylene and isoprene, contributed the most to ozone formation potential. By adopting the positive matrix factorization model, seven VOC sources were identified for both measured and initial TVOCs. Vehicular emissions, industrial sources, and biomass burning were the top three contributors to ambient TVOC. Photochemistry significantly influenced the results of source apportionment, e.g., the contribution of biogenic sources (+4.4%), industrial emissions (+2.5%) and solvent usage (+2.5%) based on initial VOCs were larger than that of measured VOCs, while the contribution of gasoline vehicular emissions (−9.9%) was lower than that of measured VOCs. Our results highlight the necessity of adequately considering the photochemical loss of VOCs for accurately apportioning the emission sources. • Photochemical reaction significantly influenced the VOC concentration. • Photochemical loss accounted for 26.3% initial alkenes and 13.1% initial aromatics. • Vehicle and combustion emissions were the largest contributors to both measured and initial VOC concentration. • Biogenic sources, industrial emissions and solvent usage based on initial VOCs were larger than that of measured VOCs. [ABSTRACT FROM AUTHOR]

We investigated the anti-inflammatory effect of trilobatin, the flavonoid isolated from the leaves of Lithocarpus polystachyus Rehd, as well as the underlying molecular mechanisms. Treatment with trilobatin (0.005-5μM) dose-dependently inhibited the lipopolysaccharide (LPS)-induced mRNA expression and secretion of pro-inflammatory cytokines, including tumor necrosis factor α (TNFα), interleukin-1β (IL-1β) and interleukin-6 (IL-6), in RAW 264.7 macrophages. However, no further inhibition was detected when the concentration of trilobatin was increased to 50μM. Western blot analysis confirmed that the mechanism of the anti-inflammatory effect was correlated with the inhibition of LPS-induced inhibitor of nuclear factor-kappa B α (IκBα) degradation and nuclear factor-kappa B (NF-κB) p65 phosphorylation. In addition, trilobatin also showed a significant inhibition of LPS-induced TNFα and IL-6 at both the mRNA and protein levels in a mouse model. Our results suggest that trilobatin potentially inhibits the LPS-induced inflammatory response by suppressing the NF-κB signaling pathway. [ABSTRACT FROM AUTHOR]

Objective: Adenoviral vector−mediated gene expression is an attractive approach to manipulate or report gene expression in human hematopoietic stem cells (HSC) when transient gene expression is preferred. Previous studies have demonstrated that fiber-retargeted Ad5F35 vectors can mediate efficient gene transfer into human HSCs. In this study, we investigated the potential of bi-directional promoter-controlled Ad5F35 vector for coordinated dual gene expression in candidate HSCs. Materials and Methods: We have engineered Ad5F35-ΔLNGFR-BiDp encoding kinase domain deleted low-affinity NGF receptor (ΔLNGFR) and green fluorescent protein (GFP) expression cassette controlled by a synthetic bi-directional promoter, which is composed of human phosphoglycerate kinase promoter and minimal core promoter from human cytomegalovirus. The expression pattern of ΔLNGFR and GFP following Ad5F35-ΔLNGFR-BiDp gene transfer in various cell types, including candidate HSCs, was compared to Ad5F35-ΔLNGFR-IRES vector encoding phosphoglycerate kinase promoter-controlled bicistronic expression cassette for ΔLNGFR and GFP. Results: Using Ad5F35-ΔLNGFR-BiDp, we demonstrated a coordinated, high-level dual gene expression in leukemic cells and cord blood CD34+ cells. However, the ability of Ad5F35-ΔLNGFR-BiDp-GFP for coordinated dual gene expression varied significantly between repopulating progenitor cells. In nonobese diabetic severe combined immune deficient mice bone marrow transplantation assay, sorted CD34+/ΔLNGFR+/GFP+ cells following infection with Ad5F35-ΔLNGFR-BiDp showed predominantly myeloid lineage reconstitution with limited lymphoid lineage differentiation capacity, whereas the CD34+/ΔLNGFR+/GFP− cells exhibited both myeloid and lymphoid reconstitution. Conclusions: This study indicates that bi-directional promoter-controlled Ad5F35 vector, such as Ad5F35-ΔLNGFR-BiDp, can be particularly useful for manipulation of myeloid progenitor cells and potentially in myeloid lineage leukemic cells as well. [Copyright &y& Elsevier]

Abstract: This paper proposes and investigates a facial feature selection and fusion technique for improving the classification accuracy of face recognition systems. The proposed technique is novel in terms of feature selection and fusion processes. It incorporates neural networks and genetic algorithms for the selection and classification of facial features. The proposed technique is evaluated by using the separate facial region features and the combined features. The combined features outperform the separate facial region features in the experimental investigation. A comprehensive comparison with other existing face recognition techniques on FERET benchmark database is included in this paper. The proposed technique has produced 94% classification accuracy, which is a significant improvement and best classification accuracy among the published results in the literature. [Copyright &y& Elsevier]

Retroviral overexpression of the transcription factor HOXB4 results in a rapid increase in proliferation of murine hematopoietic stem cells both in vivo and in vitro. Therefore, we asked whether transient overexpression of HOXB4 would increase proliferation of human primitive hematopoietic progenitors. Transient overexpression of HOXB4 was generated in umbilical cord blood (CB) CD34+ cells by a recombinant adenovirus (AdHOXB4) expressing HOXB4 together with the enhanced green fluorescent protein (GFP). Transduced, GFP+ cells were cultured in serum-free medium containing cytokines that primarily support the growth of primitive hematopoietic progenitors. In contrast to previous findings using retroviral overexpression of HOXB4, we did not observe any increase in proliferation of primitive progenitors or increased colony formation of clonogenic progenitors, including progenitor progeny from long-term culture-initiating cells following adenoviral vector overexpression of HOXB4 in CB CD34+ cells. However, enforced expression of HOXB4 by the adenoviral vector significantly increased myeloid differentiation of primitive hematopoietic progenitors. Since retroviral vectors generate low and continuous levels of transgene expression in contrast to the high, transient levels generated by the adenoviral vector, our findings suggest that the high levels of HOXB4 expression generated by AdHOXB4 in human CB CD34+ cells direct the cells toward a myeloid differentiation program rather than increased proliferation. [Copyright &y& Elsevier]

• We develop a Structured Self-attention Architecture for graph-level representation. Compared with previous GNN variants, the architecture proposed in this paper can focus more effectively on the influential part of the input graph. • The proposed architecture's readout can be incorporated into any existing node-level GNNs and provide effective features for graph-level representation. Compared with pooling readout, the proposed architecture shows its superior performance. • Extensive experiments on two types of graph datasets illustrate the effectiveness of our proposed architecture. Combining our architecture's readout with popular graph convolutional networks have validated the feasibility of structured self-attention. Recently, graph neural networks (GNNs) have shown to be effective in learning representative graph features. However, current pooling-based strategies for graph classification lack efficient utilization of graph representation information in which each node and layer have the same contribution to the output of graph-level representation. In this paper, we develop a novel architecture for extracting an effective graph representation by introducing structured multi-head self-attention in which the attention mechanism consists of three different forms, i.e., node-focused, layer-focused and graph-focused. In order to make full use of the information of graphs, the node-focused self-attention firstly aggregates neighbor node features with a scaled dot-product manner, and then the layer-focused and graph-focused self-attention serve as readout module to measure the importance of different nodes and layers to the model's output. Moreover, it is able to improve the performance on graph classification tasks by combining these two self-attention mechanisms with base node-level GNNs. The proposed Structured Self-attention Architecture is evaluated on two kinds of graph benchmarks: bioinformatics datasets and social network datasets. Extensive experiments have demonstrated superior performance improvement to existing methods on predictive accuracy. [ABSTRACT FROM AUTHOR]

SAT hydrogels exhibit a distinctive self-decomposition capability, achieving complete degradation after four weeks in a natural environment. Additionally, the supercapacitor, designed with a sandwich structure, attains a capacitance of 340.4 F g−1 at a current density of 0.8 mA cm−2. Moreover, this hydrogel can function as a flexible sensor for monitoring human joint movements, which has led to its development as a Morse code encoder. On this basis, we have developed a deep learning based assisted robotic hand gesture recognition system. [Display omitted] • The self-decomposition ability brought by starch helps promote green development. • As a supercapacitor, hydrogel has excellent capacitance performance (340 F g−1). • The hydrogel has excellent GF (3.77) when used for body sensing monitoring. • The hydrogel is developed and used as a Morse cipher compiler. • The human–computer interactive gesture recognition system is developed. Hydrogels are widely used in flexible energy storage and human state detection. As environmental protection requirements continue to increase, the degradability of hydrogels needs to be further improved. In this study, by introducing green starch into acrylamide (AM) and tannic acid (TA), the synergistic improvement of degradability, flexible energy storage and intelligent human motion state detection is achieved. These hydrogels were then assembled into supercapacitors, which achieved a capacitance of 340.4 F g−1 at a current density of 0.8 mA cm−2, with a capacitance retention rate of 83.5 % after 3000 cycles. As flexible sensing devices, the hydrogels exhibited a response time of 0.16 s and provided consistent real-time resistance change rates in response to various strains, yielding a gauge factor of 3.77. Thus, this starch based hydrogls (SAT) demonstrated promising applications as both Morse code encoders and intelligent manipulator based on deep learning, which cast lights on multifunctional flexible devices. [ABSTRACT FROM AUTHOR]

Adenovirus serotype 5 (Ad5)-based vectors can be retargeted with fiber receptor specificity of serotype 35 adenovirus (Ad5F35) and thereby bypass the paucity of the coxsackie and adenovirus receptor (CAR) on hematopoietic cells by utilizing CD46 as cellular receptor. The gene transfer efficiency into NOD/SCID repopulating cells by an Ad5F35-GFP vector was investigated in comparison with its corresponding Ad5-GFP vector. Cord blood CD34+ cells were transduced following overnight culture under serum-free conditions supported by early acting cytokines. In agreement with previous findings, the Ad5F35-GFP vector showed significant superiority to the Ad5-GFP vector in gene transfer into cells with primitive immunophenotype. However, the Ad5F35-GFP vector allowed efficient gene transfer into both dividing and nondividing CD34+ cells, whereas the Ad5-GFP vector preferentially allowed gene transfer into dividing cells expressing lower levels of CD34 antigen, which correlated with high levels of CAR expression. The sorted GFP+ cells following Ad5F35-GFP transduction at relatively low multiplicity of infection consistently reconstituted the NOD/SCID mouse bone marrow with multilineage differentiation. In contrast, the GFP+ cells following Ad5-GFP transduction were nearly devoid of reconstitution capacity. Thus, Ad5F35 vectors encoding functional genes can facilitate transient genetic manipulation of human NOD/SCID repopulating cells. [Copyright &y& Elsevier]

Aerosols have a significant impact on both direct and indirect radiative effects and are considered to be one of the largest contributors to the uncertainty in global climate change assessment. In this study, continuous one-year-round in-situ observations of aerosol optical properties were conducted in the southeastern coastal city of Xiamen, China, and the effects of chemical composition on aerosol optical properties were analyzed to assess the environmental and climate effects of aerosols. The scattering coefficient (σ sp), absorption coefficient (σ ap), single scattering albedo (SSA) showed significant seasonal variations. The σ sp and σ ap showed obvious bimodal diurnal patterns, with peaks occurring in the morning peak and evening, while the diurnal patterns of SSA were reversed. The results of the chemical component-based estimation reconstruction of σ sp illuminated that OM, NH 4 NO 3 , (NH 4) 2 SO 4 were the main contributors to the σ sp. The concentration weighted trajectory (CWT) method was used to characterize the contributing sources of each chemical component affecting σ sp. The main contributing source areas were elucidated and varied slightly with species and season. The wind dependence analysis reflected that σ ap was mainly influenced by local emissions, while σ sp was affected by both local emissions and regional transport. The contribution sources of σ sp and σ ap were investigated using potential source contribution function (PSCF) method. The contributing source of σ sp and σ ap in Xiamen were clarified, and varied slightly with seasonal differences. This study revealed the aerosol optical properties in the southeastern coastal urban areas of China and provided a scientific basis for the estimation of the factors affecting climate change. • This is the first report of one-year-round in-situ observation of the aerosol optical properties in Xiamen. • Apparent diurnal variations of the aerosol optical properties were identified. • Regional transport and local emissions were responsible for the σ sp and σ ap , respectively. • NH 4 NO 3 dominated the contribution to the σ sp in winter, while OM dominated in the other seasons. [ABSTRACT FROM AUTHOR]

Microcellular epoxy/multi-wall carbon nanotube (EP/MWCNT) composite foams loaded with 0.5, 1.0, 2.0 and 3.0 wt% of multi-walled carbon nanotubes (MWCNTs) were prepared by a batch foaming process with supercritical carbon dioxide (scCO 2 ). The morphologies of EP/MWCNT composite foams were analyzed by scanning electron microscopy (SEM). It was found that there was a synergic effect between the formation of microcellular structure and the addition of MWCNTs on improving the performances of EP/MWCNT composite foams. The addition of MWCNTs promoted the formation of microcellular structure, and the growth of cells in turn induced the redistribution of MWCNTs. Furthermore, the electromagnetic interference (EMI) shielding effectiveness (SE) of EP/MWCNT solid and foamed composites was investigated. The results indicated that the foaming improved the specific EMI SE from 5.2 to 21.3 dB cm 3 /g at the MWCNT content of 1.0 wt%. The introduction of MWCNTs and microcellular structure synergistically enhanced the EMI shielding performance of epoxy-based composites. [ABSTRACT FROM AUTHOR]

Environmental pollution of trace elements has become of main concern due to the adverse effects. To estimate the impact of PM 2.5 -bound trace elements on human health, a time-stratified case-crossover study has been designed to examine the short-term associations between 28 elements and asthma hospitalizations from January 2019 to November 2021 in Xiamen, China. This research summarized the major components that pose health risks in different seasons and took risk assessment for different groups. We found that an inter-quartile range (IQR) increase of Ca, Fe, Mn, Pd, Si, and Ti was positively associated with the incidence of asthma in the lag of 0–4 days. In winter, the elements that predisposed the population to asthma attack were the most, such as Al, Ba, Ca, Cr, Cu, Fe, K, Mn, Pd, Si, and Ti, and these elements are at higher risk for longer periods of time. The discrepancy in risk levels and major elements of asthma diagnosis among various age groups were also found in this work. Our results provided insights into the development of specific policies to reduce the risk of asthma attacks due to exposure to PM 2.5 -bound trace elements. [ABSTRACT FROM AUTHOR]

This study presents the variation of chemical components in non-refractory submicron aerosols (NR-PM 1) measured by Q-ACSM in a coastal city of Southeast China in summer and winter during the years 2017, 2018, and 2020. As we know, long-term data on aerosol chemical composition were scarce in this region. The mass concentration of NR-PM 1 decreased evidently, but the chemical composition of NR-PM 1 showed a minor variation with OA increased and NO 3 decreased over the years. PMF/ME-2 models were performed to identify OA factors resolving POA, less oxidized OOA (LO-OOA), and more oxidized OOA (MO-OOA) in this study. Secondary components made dominant contributions of 85.1%–90.7% to NR-PM 1 , and OOA became more important in aerosols with time. The SOR, NOR, and MO-OOA/LO-OOA ratio as a function of LWC and O x , combined with the diurnal variation of secondary aerosols (SAs), were performed to explore the main formation mechanism of NO 3 , SO 4 , and OOA. The results indicate that SO 4 and OOA factors in summer were mainly affected by photochemical reactions, while the characteristics and the main formation pathways of NO 3 and OOA factors in winter varied largely across the different years. The oxidized degree of OA had elevated in 2020 compared to 2017 and 2018 as the f 44 (ratio of m/z 44 to total signal) of OA increased. Our study on the annual variation of aerosol chemical composition and the dominant formation pathways of secondary components will provide a scientific reference for air quality improvement. • Chemical components in NR-PM 1 in Southeast China during 2017–2020 were presented. • Formation of sulfate and OOA in summer was dominated by photochemical reactions. • The dominant pathway for secondary aerosols in winter varied across years. • Enhanced atmospheric oxidation capacity contributed to the increasing oxidation degree of OA. [ABSTRACT FROM AUTHOR]